Azo dyestuffs



Patented Apr. 20, 1937 UNITED STATES PATENT OFFICE AZO DYESTUFFS August Modersohn, Cologne-Mulheim, and Erich Fischer, Bad Soden in Taunus, Germany, as

- signors to General Aniline Works, Inc., New

York, N. Y., a corporation of Delaware No Drawing. Application December 30, 1935, Serial No. 56,790. In Germany January 12,

4 Claims. (01. 260--44.6)

The present invention relates to azodyestuffs Example 1 derived from aminosulfones, more particularly it relates to azodyestuffs which may be represented 135 grams of the amine compound. of the forby the probable general formula: u e 5 5 H0 omsm-Q-on R-so,-oH.R -N=NR. H000 N112 CODE in which R and. R1 stand for benzene radicals, the (manufactured by condensation of o-nitrobenzyl 10 b xylic acid group a d the y y group in chloride with salicyl sulphinic acid, followed by the benzene radical R standing in o-position to reduction) are dissolved with the aid of caustic each other, and R2 stands for the radical of a soda in 1 litre of water, and to the solution 30 coupling component suitable for preparing azograms of sodium nitrite are added. Then the 13 dyestuffs, such as for a radical of a pyrazolone or solution is slowly introduced into a mixture of 15 of a sulfonic acid of a 2-naphthylamine which 300 cos. of concentrated hydrochloric acid and has been coupled in the 1-position and which may 1 kg. of ice, and to the diazo compound obtained bear further substituents, for example the hyin this manner, there is added, while stirring, at droxy group. paste of 2-amino-8-napthol-6-sulphonic acid cor- Our new dyestufis are obtainable by diazotizing responding to 120 grams of pure acid. Coupling amines of the general formula: commences even when the reaction is acid to Congo red, and, after some time, coupling is com- HO pleted by adding sodium acetate solution drop by drop. For separating the dyestuif, the reaction H000/ mixture is rendered alkaline with sodium carbonate, heated to 60 7( 0., and sodium chloride wherein R and R1 mean the same as stated is above, and coupling the same with coupling com- The dyestufi Separatw after cooling havilig i ponents suitable for preparing azodyestuffs. lts free State the follow-mg formula: 30 Favorably the components are selected in such a manner that at least one sulfonic acid group is present in the dyestuff molecule, and it is self- QCHZSOPOOH understood that the benzene nuclei R and R1 may 1 1 bear substituents, such as halogen, the alkyl, the N Q0011 II alkoxy, the nitro and. the acylarnino group. N OH In this way there are obtained yellow to violet dyestuffs of very good fastness properties, which H2N can be after-chromed on the fibre, and which are distinguished from the known dyestufis of a SO H 50 similar constitution by a better fastness to light or better levelling properties.

The starting diazotization components s d in is filtered with suction and dried. It forms a the manufacture of our new dyestu can be obredbrown powder, which dissolves in water with tained either by condensing the respective nia yellowish red and in concentrated sulfuric acid .45 trobenzyl chlorides with suitably substituted aryl with a violet coloration. The new dyestuif dyes sulfinic acids, followed by reduction, or by nitrawool, when after-treated with chromium salts, tion of suitably substituted phenyl benzyl sulfones even, clear, yellowish red shades of good fastness and reduction. properties. The following examples illustrate the invention: Dyestuffs of similar properties are obtained by 59 using as diazotizing components in the above example one of the following amino compounds:

$1 $11: Oomsm-Qon, NHz COOH I COOH (I31 HNCOCHa Dyestuffs which dye wool orange shades are obtained by using in the above example instead of the 2-amino-8-naphthol-6sulfonic acid the corresponding quantity of the Z-naphthylamine- 6- or '7-sulfonic acid. When substituting the 2- amino-B-napthol-G-sulfonic acid by the Z-meth- NHz ylamine-8-naphthol-6-sulfonic acid or the 2- ethylaminonaphthaline-7-sulfonic acid, there are obtained dyestuffs yielding more reddish shades, but having otherwise the same properties.

Example 2 100 grams of the amino compound NH: GOOH (manufactured by condensation of o-chlorobenzyl compound thus obtained is coupled, in aqueous medium alkaline with sodium carbonate, with 85 grams of 1(2'-ohlorophenyl) -3-methyl-5-pyrazolone- -sulfonic acid.

The dyestuif having in its free state the following formula:

lo I l HOgS- I omsolon, CHa-OCHzSOz-QOH,

NHZ

| oHlsoP OH or Q omsorgon is separated with sodium chloride. The dyestuif, when dried, forms a yellow powder which dissolves coon COOH

in water and in concentrated sulfuric acid with a yellow coloration. The dyestuff dyes wool, when after-treated with chromium salts, even, clear, greenish yellow shades of good fastness properties.

On substituting the amino compound used in Example 2 by C0011 I THz COOH Example 3 3&9 grams of the amino compound of the following formula:

(manufactured by condensation of 3-nitro-4- methoxy-l-benzyl chloride with cresotin sulfinic acid, followed by reduction with iron and acetic acid) are dissolved in hot water and 400 005. of hydrochloric acid. The clear solution is slowly introduced into a mixture of hydrochloric acid and ice, contemporaneously an aqueous solution of 70 grams of sodium nitrite being introduced in such a manner that during the whole process there is present a small excess of the nitrite. The diazo compound separated is filtered with suction and added slowly to a solution of 98 grams of 3-methyl-5-pyrazolone alkaline with sodium. To the solution of the dyestuff common salt is added while heating, whereby the dyestuff having in its free state the following formula:

CIEIH no-C s ozonrQoom COOH If I N-ono-o11.

separates in a form well suitable for being filtered ofi. After drying it represents a yellow powder, soluble in water with a' yellow coloration. When dyed on wool and chromed according to the one 5 bath process reddish yellow shades of good fastness properties are obtained.

Example 4 85 grams of 2-amino-8-naphthol-6-sulfonic acid are dissolved in 1.5 litres of water with the addition of caustic soda, and while cooling reprecipitated in a finely divided form by adding the calculated quantity of hydrochloric acid. To the suspension there is added while stirring and cooling a diazo solution obtained by diazotizing with the calculated quantity of nitrosyl sulfuric acid 102 grams of 2-amino-5-nitrobenzyl-4-hydroxy 5'-carboxy-phenylsulfone in 200 grams of concentrated sulfuric .acid. Coupling already begins at strongly acid reaction and is completed in a short time by addition of sodium acetate solution. The dyestuff obtained having in its free state the following formula:

1%: COOH f 0H SOBH is filtered with suction, redissolved in water with the aid of soda and separated in the usual manner by salting out. The dried dyestuiT is obtained in form of a nearly black powder dissolving in water with a reddish-violet, in concentrated sulfuric acid with a wine-red coloration. It dyes wool when afterchromed violet shades.

The 2-amino-5-nitrobenzyl-4-hydroXy-5'-carboxyphenylsulfone of the formula:

|N112 (IJOOH can be prepared by heating the 2-chloro-5-nitrobenzyl-4-hydroXy-5carboxyphenylsulfone with ammonia under pressure, whereby the chlorine is substituted by the amino group. F We claim: 1. Dyestuffs having in the free state the following formula:

R--SO2'CHz-R1N=NR2 6O HOOC/ in which R and R1 stands for benzene radicals, the carboxylic acid group and the hydroxy group in the benzene radical R standing in o-position to each other, and R2 stands for a radical of a coupling component of the group consisting of pyrazolones and Z-naphthylamine sulfonic acids which have been coupled in the 1-position, dyeing 5 the animal fibre generally yellow to violet shades of good fastness properties when after-chromed.

2. The dyestufi having in its free state the fol lowing formula:

BEN-

SOQH

dyeing wool, when aftertreated with chromium '20 salts, even, clear, yellowish-red shades of good fastness properties.

3. The dyestufi having in its free state the following formula: o 2o I OH.SO. OH

1?: (icon 30 N(IJH('JI-GHa Bossyielding on wool, when dyed and chromed according to the one bath process reddish-yellow shades of good fastness properties.

AUGUST MODERSOHN. ERICH FISCHER. 

